CVE-2026-93355: berriai litellm Weak Authentication

Vulnerability summary

CVE-2026-93355 is a high (CVSS 8.1) Weak Authentication vulnerability in berriai litellm. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 18.5% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 28-09-2026
   PublishedVulnerability first disclosed.
2. 01-10-2026
   Last modifiedVulnerability information updated.

Description

LiteLLM contains a weak authentication vulnerability that allows an attacker holding a valid JWT from the configured identity provider to authenticate as any existing user by exploiting an email-based fallback lookup in the JWT authentication flow without verifying the email_verified claim. Attackers can present a token with an unverified email address matching a victim's account to inherit the victim's role, including proxy_admin privileges, and permanently overwrite the victim's stored identity binding to retain persistent unauthorized access to administrative endpoints exposing API keys and user management.

• CWE-1390Weak AuthenticationThe product uses an authentication mechanism to restrict access to specific users or identities, but the mechanism does not sufficiently prove that the claimed identity is correct.